Flavors are used as adjunctives in many food and non-food products. Typically, flavors are added to confections, chewing gums, dentifrices, and so forth. More recently the application of encapsulating techniques has been applied to flavors to prolong, delay, or otherwise enhance the flavor agent's perception by the user of the product containing it.
U.S. Pat. No. 3,957,964 teaches a dentifrice containing encapsulated flavors wherein various material and synthetic polymers are used as the encapsulating medium for the polymer.
Slow release flavors entrapped in edible gels are disclosed for use in chewing gums in U.S. Pat. No. 3,920,849. Similarly, U.S. Pat. No. 3,761,286 teaches the use of encapsulated flavors in chewing gum, toothpaste and foods. The encapsulating medium is a hydroxymethyl methacrylate.
Other approaches to the encapsulation of flavors for delayed or sustained release are known to the art. For example, U.S. Pat. No. 3,201,353 discloses microinclusion containing flavors in chewing gums. U.S. Pat. No. 3,011,949 utilizes liquid sugar for coating solid particles of flavor and uses the dried, pulverized flavor material in chewing gum. Other techniques have utilized gelatin-encapsulated flavors (U.S. Pat. No. 2,886,446) and gelatin-concentrated flavors (U.S. Pat. No. 2,886,444) for use in chewing gums.
In addition to gelatin, the art discloses as encapsulating media gum arabic, ethyl cellulose modified starches, starch hydrolysates, hydrophilic colloids or combinations thereof; see for example U.S. Pat. Nos. 3,850,838; 3,930,026; 3,962,463; and 4,316,915. Generally, the teachings relating to hydrophillic colloids describe the absorption of flavors onto hydrocolloids or spray drying the flavors in an aqueous hydrocolloid/flavor matrix.
Calcium alginate is disclosed as a coating material for flavor particles in U.S. Pat. No. 3,857,964. Other patents which disclose the use of alginates as an encapsulating medium are U.S. Pat. Nos. 3,985,913 and 4,238,475.
European patent application No. 81,392,918.3 discloses a method for preparing calcium alginate fibers which are alleged to be useful in encapsulating flavors.
A delayed release sodium fluoride formula encapsulated in a pretreated ethyl cellulose is taught in U.S. Pat. No. 4,220,552. The ethyl cellulose is hydrochloric acid treated prior to use.